Journal of Applied Science and Engineering

Published by Tamkang University Press

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Swelling of Steels Subjected to Fast Neutrons’ Irradiation using Optimized Ensemble Regressions

 2027

 Volume 36

Ziqi Ren1,2,3,4, Yaping Zhao1,3, Baoxiu Li1,2,3, and Zixuan Zhang1,3

1Department of Materials and Construction Engineering, Hebei Institute of Mechanical and Electrical Technology, Xingtai City, Hebei Province, 054000, China

2Hebei Science Popularization Base for Additive Manufacturing, Xingtai City, Hebei Province, 054000, China

3Hebei Technology Innovation Centre for New Energy Vehicle Integrated Die Casting, Xingtai City, Hebei Province, 054000, China

4Xingtai Green Digital Precision Casting Technology Innovation Center, Xingtai City, Hebei Province, 054000, China

Received: June 22, 2026
Accepted: September 20, 2026
Publication Date: October 26, 2026

上傳圖片

Introduced input parameters’ box plot to estimate Swe

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Radiation-induced swelling (swe) of structural steels under fast neutron irradiation is a critical degradation phenomenon that limits the service lifetime and safety of nuclear reactor components. Conventional experimental approaches for evaluating swelling behavior are costly, time-consuming, and difficult to apply under high-dose irradiation conditions. This study develops an optimized machine learning framework for predicting the swelling behavior of austenitic steels exposed to fast neutron irradiation. A dataset containing 444 experimental samples collected from published literature was established, including twelve input variables related to chemical composition (Fe, Cr, Ni, Mo, Mn, C, Ti, Si, and P), cold work degree, irradiation dose, and temperature. Two ensemble regression models, Adaptive Boosting Regression (ABR) and Extra Tree Regression (ETR), were optimized using the Tyrannosaurus Rex Optimization (TRO) algorithm to improve hyperparameter selection and prediction performance. The dataset was randomly divided into 75% training data (333 samples) and 25% testing data (111 samples), with preprocessing methods including normalization, randomization, interquartile range (IQR)-based outlier treatment, and four-fold cross-validation applied to enhance model reliability. The optimized Extra Tree Regression model (ExtraT-T) achieved superior predictive performance, obtaining coefficients of determination (R2) of 0.9908 and 0.9563 for the training and testing datasets, respectively, compared with 0.9679 and 0.8991 for the optimized ABR model (AdaB-T). Feature analysis revealed that irradiation dose and cold work degree were the dominant factors affecting swelling behavior[cite: 80]. The proposed optimized machine learning framework provides an efficient approach for predicting radiation-induced swelling, reducing dependence on irradiation experiments, and supporting the design of radiation-resistant nuclear materials.

Keywords: SWE; Neutrons; Irradiation; Austenitic steel; ML; Boosting algorithms

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